Description. Morphometric data are given in Table 1 and a summary of meristic data appears in Table 2. A moderate to small-sized species of Bryconops , known from specimens less than 70 mm SL. Overall body shape with convex dorsum and slightly rounded belly, tapering to relatively short and deep caudal peduncle 10.5-13.9 (12.0 % SL). Dorsal fin origin at level of pelvic origin, almost at center of the body 49.0-52.3 (50.5 % SL).

Pigmentation in alcohol. Overall moderate dusky species in preservation, countershaded above and below lateral stripe. Dorsal profile of head dark, fully covered with fine melanophores homogeneously distributed. Anterior area of mouth dark. Nares not covered with pigment. Orbit with a black dorsal band. Infraorbitals and preopercle sparsely pigmented, more conspicuous at sutures. Opercle with star-like diffused spots, more evident in dorsal region. Lateral stripe originating just behind head, somewhat prominent in preservation; increasing in depth and intensity just posterior to dorsal fin origin, occupying three to four scale rows just behind midbody and ending in darker, oblong-shaped expansion just anterior to caudal fin. Centers of upper lateral scales pigmented densely. First 14 scales of lateral line canal outlined with pigment. Below lateral line, melanophores distributed along myosepta from just anterior to anus to midpoint of anal fin. Anal-fin base with a diffuse basal band formed by series of melanophores along pterygiophores. Dorsal, pectoral, and pelvic fins with melanophores outlining lower portion of fin rays. Adipose fin lacking melanophores. Both lobes of caudal fin densely covered by melanophores. A clear but diffuse area on anterobasal part of upper caudal lobe, not forming a well-defined ocellus. Distal margin of caudal fin area with a dark, almost black terminal band, especially on upper lobe.

Coloration in life (Fig. 3c). Body usually grayish or metallic dorsolaterally, becoming silvery toward lateral and ventral flanks. A black lateral stripe extends from opercular opening to caudal fin base. Below this stripe there is a wider silvery stripe, limited dorsally by an iridescent metallic-yellow stripe.

Distribution. This new species is only known from the type locality, the Río Moquete, Anzoátegui State, Venezuela. The Río Moquete is a northern tributary of the Río Orinoco.

Habitat. Bryconops magoiZBK is known only from a morichal with fast moving waters over sandy bottoms. This species frequently is found in water from mid-depth to the surface, at the center of the main channel, where it schools with other characid species. Individuals feed at the surface and are attracted to allotochtonus material that falls into the water. Cursory examination shows that they feed on several groups of terrestrial insects.

Etymology. The species-group name, magoi, is dedicated to the memory of Dr. Francisco Mago-Leccia, pioneer of modern ichthyological studies in Venezuela.

Comparison with B. colletteiZBK . Bryconops magoiZBK differs in body shape from B. colletteiZBK . The results of sheared principal components analysis and relative warp analysis show that all individuals of both species are discriminated by either the second sheared principal component (Fig. 6) or by the first relative warp. In both analyses all individuals of B. magoiZBK fell at, or inside, the boundary of the 95% confidence ellipse, whereas three individuals of B. colletteiZBK fell just outside the 95% confidence ellipse, but with a morphology most different from B. magoiZBK (Fig. 6). The first two eigenvectors of the PCA described 99.1% of the variance. The second sheared PC identified a contrasting suite of traits such that B. magoiZBK has a longer snout and B. colletteiZBK has a longer anal fin base, a larger orbit, and a greater distance between the dorsal fins (Fig. 7). RWA produced identical results to the PCA. Even though individuals of B. colletteiZBK from the Río Iguapo have slightly longer snouts relative to other populations, there is no overlap in snout length between the species. For each of the other metric traits the differences between the species are statistically significant, but there is some overlap between the species.

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Biology

Collected from a morichal with fast moving waters over sandy bottoms; often in water from mid-depth to the surface, at the center of the main channel, where it schools with other characid species. Feeds at the surface and attracted to allotochtonus material that falls into the water; also on several groups of terrestrial insects (Ref. 56366).

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Diagnostic Description

Diagnosis: Differs from its congeners, except collettei, by its unique color pattern, red coloration at the upper half of a diffuse caudal fin ocellus. Further distinguished from other species of the subgenus Bryconops by the following characters: pored lateral scales 43-47, modally 44 or 45 (vs. >57 in alburnoides,